diff --git a/ege/Environement.hpp b/ege/Environement.hpp
index 428d1da..aaa4905 100644
--- a/ege/Environement.hpp
+++ b/ege/Environement.hpp
@@ -70,6 +70,7 @@ namespace ege {
 				m_groupSource(_groupSource),
 				m_positionSource(_pos)
 			{ };
+			virtual ~EntityInteraction() = default;
 		public:
 			virtual void applyEvent(ege::Entity& _entity) { };
 	};
diff --git a/ege/physics/Component.cpp b/ege/physics/Component.cpp
index f36cdf9..5baa1c4 100644
--- a/ege/physics/Component.cpp
+++ b/ege/physics/Component.cpp
@@ -13,6 +13,9 @@
 #include <ege/physics/shape/ConvexHull.hpp>
 #include <ege/physics/shape/Cylinder.hpp>
 #include <ege/physics/shape/Sphere.hpp>
+#include <ege/physics/shape/Concave.hpp>
+#include <ephysics/collision/shapes/ConcaveShape.h>
+#include <ephysics/collision/shapes/ConcaveMeshShape.h>
 
 const std::string& ege::physics::Component::getType() const {
 	static std::string tmp("physics");
@@ -63,7 +66,13 @@ ege::physics::Component::Component(ememory::SharedPtr<ege::Environement> _env, c
 	EGE_ERROR("Bounciness=" << m_rigidBody->getMaterial().getBounciness());
 	EGE_ERROR("FrictionCoefficient=" << m_rigidBody->getMaterial().getFrictionCoefficient());
 	EGE_ERROR("RollingResistance=" << m_rigidBody->getMaterial().getRollingResistance());
-	m_rigidBody->getMaterial().setFrictionCoefficient(0.5);
+	EGE_ERROR("LinearDamping=" << m_rigidBody->getLinearDamping());
+	EGE_ERROR("AngularDamping=" << m_rigidBody->getAngularDamping());
+	m_rigidBody->getMaterial().setBounciness(0.4);
+	//m_rigidBody->getMaterial().setFrictionCoefficient(0.01);
+	//m_rigidBody->getMaterial().setRollingResistance(0.01);
+	m_rigidBody->setAngularDamping(0.9);
+	m_rigidBody->setLinearDamping(0.9);
 }
 
 void ege::physics::Component::setType(enum ege::physics::Component::type _type) {
@@ -117,7 +126,7 @@ void ege::physics::Component::generate() {
 				                                tmpElement->getSize().y(),
 				                                tmpElement->getSize().z());
 				// Create the box shape
-				rp3d::BoxShape* shape = new rp3d::BoxShape(halfExtents);
+				rp3d::BoxShape* shape = new rp3d::BoxShape(halfExtents, 0.0001);
 				m_listShape.push_back(shape);
 				rp3d::Vector3 position(it->getOrigin().x(),
 				                       it->getOrigin().y(),
@@ -230,24 +239,52 @@ void ege::physics::Component::generate() {
 				m_listProxyShape.push_back(proxyShape);
 				break;
 			}
-			case ege::physics::Shape::type::convexHull: {
-				EGE_DEBUG("    convexHull");
-				const ege::physics::shape::ConvexHull* tmpElement = it->toConvexHull();
+			case ege::physics::Shape::type::concave: {
+				EGE_DEBUG("    Concave");
+				const ege::physics::shape::Concave* tmpElement = it->toConcave();
 				if (tmpElement == nullptr) {
-					EGE_ERROR("    convexHull ==> can not cast in convexHull");
+					EGE_ERROR("    Concave ==> can not cast in Concave");
 					continue;
 				}
+				
+				float* vertices = (float*)&tmpElement->getVertex()[0];
+				int* indices = (int*)&tmpElement->getIndices()[0];
+				
+				int32_t nbVertices = tmpElement->getVertex().size();
+				int32_t nbTriangles = tmpElement->getIndices().size()/3;
+				// TODO : Manage memory leak ...
+				//we have an error here ...
+				
+				rp3d::TriangleVertexArray* triangleArray = new rp3d::TriangleVertexArray(nbVertices,
+				                                                                         vertices,
+				                                                                         4 * sizeof(float),
+				                                                                         nbTriangles,
+				                                                                         indices,
+				                                                                         sizeof(int32_t),
+				                                                                         rp3d::TriangleVertexArray::VERTEX_FLOAT_TYPE,
+				                                                                         rp3d::TriangleVertexArray::INDEX_INTEGER_TYPE);
+				// Now that we have a TriangleVertexArray, we need to create a TriangleMesh and add the TriangleVertexArray into it as a subpart.
+				// Once this is done, we can create the actual ConcaveMeshShape and add it to the body we want to simulate as in the following example:
+				rp3d::TriangleMesh triangleMesh;
+				// Add the triangle vertex array to the triangle mesh
+				triangleMesh.addSubpart(triangleArray);
+				// Create the concave mesh shape
 				/*
-				btConvexHullShape* tmpShape = new btConvexHullShape(&(tmpElement->getPointList()[0].x()), tmpElement->getPointList().size());
-				if (tmpShape != nullptr) {
-					if (outputShape == nullptr) {
-						return tmpShape;
-					} else {
-						vec4 qqq = tmpElement->getQuaternion();
-						const btTransform localTransform(btQuaternion(qqq.x(),qqq.y(),qqq.z(),qqq.w()), tmpElement->getOrigin());
-						outputShape->addChildShape(localTransform, tmpShape);
-					}
-				}
+				// TODO : Manage memory leak ...
+				reactphysics3d::ConcaveShape* shape = new reactphysics3d::ConcaveMeshShape(&triangleMesh);
+				rp3d::Vector3 position(it->getOrigin().x(),
+				                       it->getOrigin().y(),
+				                       it->getOrigin().z());
+				rp3d::Quaternion orientation(it->getQuaternion().x(),
+				                             it->getQuaternion().y(),
+				                             it->getQuaternion().z(),
+				                             it->getQuaternion().w());
+				// The ephysic use Y as UP ==> ege use Z as UP
+				orientation = orientation * rp3d::Quaternion(-0.707107, 0, 0, 0.707107);
+				rp3d::Transform transform(position, orientation);
+				rp3d::ProxyShape* proxyShape = m_rigidBody->addCollisionShape(shape, transform, it->getMass());
+				proxyShape->setUserData(this);
+				m_listProxyShape.push_back(proxyShape);
 				*/
 				break;
 			}
diff --git a/ege/physics/shape/Concave.cpp b/ege/physics/shape/Concave.cpp
new file mode 100644
index 0000000..dc728bb
--- /dev/null
+++ b/ege/physics/shape/Concave.cpp
@@ -0,0 +1,16 @@
+/** @file
+ * @author Edouard DUPIN
+ * @copyright 2011, Edouard DUPIN, all right reserved
+ * @license MPL v2.0 (see license file)
+ */
+#include <ege/debug.hpp>
+#include <ege/physics/shape/Concave.hpp>
+
+
+
+bool ege::physics::shape::Concave::parse(const char* _line) {
+	if (ege::physics::Shape::parse(_line) == true) {
+		return true;
+	}
+	return false;
+}
diff --git a/ege/physics/shape/Concave.hpp b/ege/physics/shape/Concave.hpp
new file mode 100644
index 0000000..c5917a8
--- /dev/null
+++ b/ege/physics/shape/Concave.hpp
@@ -0,0 +1,66 @@
+/** @file
+ * @author Edouard DUPIN
+ * @copyright 2011, Edouard DUPIN, all right reserved
+ * @license MPL v2.0 (see license file)
+ */
+#pragma once
+
+
+#include <etk/types.hpp>
+#include <ege/physics/shape/Shape.hpp>
+
+
+namespace ege {
+	namespace physics {
+		namespace shape {
+			class Concave : public ege::physics::Shape {
+				public:
+					Concave() {};
+					virtual ~Concave() {};
+				public:
+					virtual bool parse(const char* _line);
+					virtual void display() {};
+				public:
+					virtual enum ege::physics::Shape::type getType() const {
+						return ege::physics::Shape::type::concave;
+					}
+				public:
+					virtual const ege::physics::shape::Concave* toConcave() const {
+						return this;
+					}
+					virtual ege::physics::shape::Concave* toConcave() {
+						return this;
+					}
+				private:
+					std::vector<vec3> m_listVertex;
+					std::vector<int> m_indices; // TODO : do it better: this is dependent of ephysics
+				public:
+					void clear() {
+						m_listVertex.clear();
+						m_indices.clear();
+					}
+					void setListOfVertex(const std::vector<vec3>& _listVertex) {
+						m_listVertex = _listVertex;
+					}
+					void addTriangle(const std::vector<uint32_t>& _index) {
+						/*
+						if (m_indices.size() == 0) {
+							m_indices = _index;
+							return;
+						}
+						*/
+						for (auto &it: _index) {
+							m_indices.push_back(it);
+						}
+					}
+					const std::vector<vec3>& getVertex() const {
+						return m_listVertex;
+					}
+					const std::vector<int>& getIndices() const {
+						return m_indices;
+					}
+			};
+		}
+	}
+}
+
diff --git a/ege/physics/shape/ConvexHull.cpp b/ege/physics/shape/ConvexHull.cpp
index 2928499..347be02 100644
--- a/ege/physics/shape/ConvexHull.cpp
+++ b/ege/physics/shape/ConvexHull.cpp
@@ -31,6 +31,7 @@ bool ege::physics::shape::ConvexHull::parse(const char* _line) {
 			EGE_VERBOSE("    parsed " << m_points[iii]);
 		}
 		*/
+		
 		return true;
 	}
 	if(strncmp(_line, "scale:", 6) == 0) {
diff --git a/ege/physics/shape/Shape.cpp b/ege/physics/shape/Shape.cpp
index f754468..9d55511 100644
--- a/ege/physics/shape/Shape.cpp
+++ b/ege/physics/shape/Shape.cpp
@@ -11,6 +11,7 @@
 #include <ege/physics/shape/ConvexHull.hpp>
 #include <ege/physics/shape/Cylinder.hpp>
 #include <ege/physics/shape/Sphere.hpp>
+#include <ege/physics/shape/Concave.hpp>
 
 
 ememory::SharedPtr<ege::physics::Shape> ege::physics::Shape::create(const std::string& _name) {
@@ -28,8 +29,10 @@ ememory::SharedPtr<ege::physics::Shape> ege::physics::Shape::create(const std::s
 		tmpp = ememory::makeShared<ege::physics::shape::Capsule>();
 	} else if (name == "convexhull") {
 		tmpp = ememory::makeShared<ege::physics::shape::ConvexHull>();
+	} else if (name == "autoconcave") {
+		tmpp = ememory::makeShared<ege::physics::shape::Concave>();
 	} else {
-		EGE_ERROR("Create an unknow element : '" << _name << "' availlable : [BOX,SPHERE,CONE,CYLINDER,CAPSULE,CONVEXHULL]");
+		EGE_ERROR("Create an unknow element : '" << _name << "' availlable : [BOX,SPHERE,CONE,CYLINDER,CAPSULE,CONVEXHULL,autoConcave]");
 		return nullptr;
 	}
 	if (tmpp == nullptr) {
diff --git a/ege/physics/shape/Shape.hpp b/ege/physics/shape/Shape.hpp
index 33ada00..bab86ee 100644
--- a/ege/physics/shape/Shape.hpp
+++ b/ege/physics/shape/Shape.hpp
@@ -21,6 +21,7 @@ namespace ege {
 			class Cone;
 			class ConvexHull;
 			class Sphere;
+			class Concave;
 		}
 		
 		class Shape {
@@ -34,7 +35,8 @@ namespace ege {
 					cone,
 					convexHull,
 					cylinder,
-					sphere
+					sphere,
+					concave
 				};
 			public:
 				Shape() :
@@ -97,6 +99,9 @@ namespace ege {
 				bool isSphere() {
 					return getType() == ege::physics::Shape::type::sphere;
 				};
+				bool isConcave() {
+					return getType() == ege::physics::Shape::type::concave;
+				};
 				
 				virtual const ege::physics::shape::Box* toBox() const {
 					return nullptr;
@@ -139,6 +144,12 @@ namespace ege {
 				virtual ege::physics::shape::Sphere* toSphere() {
 					return nullptr;
 				};
+				virtual const ege::physics::shape::Concave* toConcave() const {
+					return nullptr;
+				};
+				virtual ege::physics::shape::Concave* toConcave() {
+					return nullptr;
+				};
 		};
 	}
 }
diff --git a/ege/resource/Mesh.cpp b/ege/resource/Mesh.cpp
index ba573e9..030822e 100644
--- a/ege/resource/Mesh.cpp
+++ b/ege/resource/Mesh.cpp
@@ -398,9 +398,9 @@ void ege::resource::Mesh::generateVBO() {
 	}
 	EGE_WARNING("Generate VBO for nb faces layers: " << m_listFaces.size() << " list layer=" << etk::to_string(m_listFaces.getKeys()));
 	
-	// generate element in 2 pass : 
-	//    - create new index dependeng a vertex is a unique componenet of position, texture, normal
-	//    - the index list generation (can be dynamic ... (TODO later)
+	// generate element in 2 pass:
+	//    - create new index depending on a vertex is a unique component of position, texture, normal
+	//    - the index list generation (can be dynamic ... (TODO later))
 	for (int32_t kkk=0; kkk<m_listFaces.size(); kkk++) {
 		// clean faces indexes :
 		m_listFaces.getValue(kkk).m_index.clear();
@@ -711,3 +711,26 @@ void ege::resource::Mesh::addTriangle(const std::string& _layerName, const vec3&
 		return;
 	}
 }
+
+#include <ege/physics/shape/Concave.hpp>
+const std::vector<ememory::SharedPtr<ege::physics::Shape>>& ege::resource::Mesh::getPhysicalProperties() {
+	for (auto &it: m_physics) {
+		if (it->getType() == ege::physics::Shape::type::concave) {
+			// need to generate the internal list of point and triangle needed:
+			ege::physics::shape::Concave* tmpElement = it->toConcave();
+			if (tmpElement == nullptr) {
+				EGE_ERROR("    Concave ==> can not cast in Concave");
+				return m_physics;
+			}
+			tmpElement->clear();
+			tmpElement->setListOfVertex(m_listVertex);
+			for (int32_t kkk=0; kkk<m_listFaces.size(); kkk++) {
+				tmpElement->addTriangle(m_listFaces.getValue(kkk).m_index);
+			}
+			// Can have only one concave element in a mesh ...
+			return m_physics;
+		}
+	}
+	return m_physics;
+}
+
diff --git a/ege/resource/Mesh.hpp b/ege/resource/Mesh.hpp
index ab80ee5..dab3631 100644
--- a/ege/resource/Mesh.hpp
+++ b/ege/resource/Mesh.hpp
@@ -28,6 +28,20 @@
 
 namespace ege {
 	namespace resource {
+		/* TODO: A mesh is composed with:
+		 *     - a geometric property:
+		 *         * list of points
+		 *         * list of normals
+		 *         * List of texture UV mapping
+		 *         + List of triangle
+		 *         + List of quad
+		 *         + List of polygones
+		 *     - List of material
+		 *     - Physics shapes
+		 *     - UV texture
+		 *     - Normal texture
+		 *     - open GL shaders
+		 */
 		class Mesh : public gale::Resource {
 			public:
 				static ememory::SharedPtr<ege::resource::Mesh> createGrid(int32_t _lineCount,
@@ -149,9 +163,7 @@ namespace ege {
 				bool getCheckNormal() {
 					return m_checkNormal;
 				};
-				const std::vector<ememory::SharedPtr<ege::physics::Shape>>& getPhysicalProperties() const {
-					return m_physics;
-				};
+				const std::vector<ememory::SharedPtr<ege::physics::Shape>>& getPhysicalProperties();
 				void addPhysicElement(const ememory::SharedPtr<ege::physics::Shape>& _shape) {
 					m_physics.push_back(_shape);
 				}
diff --git a/lutin_ege.py b/lutin_ege.py
index 82934ec..702863e 100644
--- a/lutin_ege.py
+++ b/lutin_ege.py
@@ -72,6 +72,7 @@ def configure(target, my_module):
 	    'ege/physics/shape/ConvexHull.cpp',
 	    'ege/physics/shape/Cylinder.cpp',
 	    'ege/physics/shape/Sphere.cpp',
+	    'ege/physics/shape/Concave.cpp',
 	    'ege/Ray.cpp',
 	    ])
 	my_module.copy_path('data/ParticuleMesh.*')
@@ -121,6 +122,7 @@ def configure(target, my_module):
 	    'ege/physics/shape/ConvexHull.hpp',
 	    'ege/physics/shape/Cylinder.hpp',
 	    'ege/physics/shape/Sphere.hpp',
+	    'ege/physics/shape/Concave.hpp',
 	    'ege/Ray.hpp',
 	    ])
 	# TODO: Remove this ...